Propyl gallate

Propyl gallate was the offending agent in Alphosyl cream, causing allergic contact dermatitis in a psoriatic patient after 1.5 years use (Liden 1975). It appears that 1 % in petrolatum is a satisfactory patch test concentration. 

BP Propyl gallate PhEur Propylis gallas USPNF Propyl gallate 

Propyl gallate is a white, odorless or almost odorless crystalline powder, with a bitter astringent taste that is not normally noticeable at the concentrations employed as an antioxidant. 

E310 gallic acid propyl ester n-propyl gallate Progallin P propyl 3,4,5-trihydroxybenzoate Tenox PG. 

Propyl gallate has become widely used as an antioxidant in cosmetics, perfumes, foods, and pharmaceuticals since its use in preventing autoxidation of oils was first described in 1943. It is primarily used, in concentrations up to 0.1% w/v, to prevent the rancidity of oils and fats it may also be used at concentrations of 0.002% w/v to prevent peroxide formation in ether, and at 0.01% w/v to prevent the oxidation of paraldehyde. Synergistic effects with other antioxidants such as butylated hydroxyanisole and butylated hydroxytoluene have been reported. Propyl gallate is also said to possess some antimicrobial properties see Section 10. 

Studies have shown that, when added to powder blends containing ketorolac, propyl gallate significantly increases the drug stability in the preparation.  

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FLUORINECOMPOUNDS,ORGANIC - FLUORINATED ALIPHATIC COMPOUNDS] (Vol 11) n-Propyl gallate [129-79-9]... 

Antioxidants (qv) have a positive effect on oils when present in the proper concentration. Sterols and tocopherols, which are natural antioxidants, may be analy2ed by gas-Hquid chromatography (glc), high performance Hquid chromatography (hplc), or thin-layer chromatography (tic). Synthetic antioxidants maybe added by processors to improve the performance or shelf life of products. These compounds include butylatedhydroxyanisole (BHA), butylated hydroxytoluene (BHT), / fZ-butyUiydroquinone (TBHQ), and propyl gallate. These materials may likewise be analy2ed by glc, hplc, or tic. Citric acid (qv), which functions as a metal chelator, may also be deterrnined by glc. 

BHA and BHT, which are both fat soluble, are effective ia protecting animal fat from oxidation, and are often added duting the rendering process. Propyl gallate is also effective, but it has limited fat solubiUty, and turns bluish black ia the presence of iron. It is typically used as a synergist ia combination with BHA or BHT. TBHQ is most effective against oxidation ia polyunsaturated vegetable oils (qv), and is often used ia soybean oil (19). 

Gallic acid propyl ester N-propyl gallate propyl 3,4,5-trihydroxy-benzoate... 

Propyl gallate is an antioxidant. It protects against oxidation by hydrogen peroxide and oxygen free radicals in a catalytic manner similar to superoxide dismutase. 

Propyl gallate is used to protect oils and fats in products from oxidation. It is used in foods, cosmetics, hair products, adhesives, and lubricants. 

See also sugars gallic acid. See propyl gallate gasoline, 228... 

Antioxidants are not important only to the health conscious food manufacturers also rely on these chemicals to maintain the shelf life of their products. Synthetic antioxidants such as butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate and tert-butyl hydroquinone were widely used in food processing to control oxidation and maintain food quality. However, as these synthetic antioxidants are suspected to be carcinogenic they now have restricted use in food (Madahavi and Salunkhe, 1995). Therefore, natural antioxidant sources, especially of plant origin, are of great interest to the food industry. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

The commonest synthetic antioxidants are butylated hydroxyanisole (BHA) and butylated hydroxy toluene (BHT). Other synthetic antioxidants are w-propyl gallate and n-octyl gallate. Any substance that can act as a radical trap will have antioxidant properties. There are strict rules governing the use of antioxidants in foods. Only those substances that are on the permitted list can be used. 

Propyl gallate, antioxidant useful in cosmetics, 7 830t Propylparaben... 

Annex III lays down the conditions of use for permitted preservatives and antioxidants, with lists of foods and maximum levels in each case. Part A lists the sorbates, benzoates and p-hydroxybenzoates, E 200-E 219 part B lists sulphur dioxide and the sulphites, E 220-E 228 part C lists other preservatives with their uses, including nisin, dimethyl dicarbonate and substances allowed for surface treatment of certain fruits, E 249 potassium nitrite, E 250 sodium nitrite, E 251 sodium nitrate and E 252 potassium nitrate, E 280-E 283 propionic acid and the propionates part D lists the antioxidants E 320 butylated hydroxyanisole (BHA), E 321 butylated hydroxytoluene (BHT), E 310 propyl gallate, E 311 octyl gallate, E 312 dodecyl gallate, E 315 eiythorbic acid and E 316 sodium erythorbate. 

Hydroxymethyl-2,6-di-fert-butylphenol Propyl gallate Stannous chloride TBHQ (tertiarybutylhydroquinone)... 

Propyl gallate, BHA, BHT, TBHQ, THBP, 4-hydroxymethyl-2,6-di-ferf-butylphenol, thiodipropionic acid and dilauiylthiodipropionic acid may be used provided that the total antioxidant content does not exceed 200 mg kg"1 of the fat or oil content when used according to good manufacturing practice. Anoxomer may be used provided that the total antioxidant content does not exceed 5000 mg kg 1 of the fat or oil content of the food. 

One of the most important advantages of HPLC over spectrophoto-metric methods lies in its specificity and selectivity due to its separation capability. Through chromatographic separations, the analytes of interest can be detected and quantified without interference from the typical matrix that includes excipients, antioxidants, preservatives, and dissolution media. Ion-pair HPLC was used to monitor the dissolution of pentamidine from EVA sustained-release film where polymeric matrices could create significant bias if a spectrophotometric method were used. Due to their strong UV absorbance, the antioxidants and preservatives (e.g., BHA, BHT, ascorbic acid and propyl gallate) are often the major... 

Giloh, H. and Sedat, M. (1982) Fluorescence microscopy reduced photobleaching of rhodamine and fluorescein protein conjugates by A-propyl gallate. Science 217, 1252-1255. 

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